Python：嵌套 {dict : {dict : [list] } } 结构和正则表达式匹配的问题

Question

我一直在试图找出我在使用嵌套字典/列表时遇到的问题。

import re
sentence_list = ["the quick brown fox", "ellie the elephant", "the lion, the witch and the wardrobe", "lion and tiger and elephant, oh my!"]

animal_dict = {"lion":[], "fox":[], "tiger":[], 'elephant':[]}

sentence_dict = {}

for s in sentence_list:
    sentence_dict[s] = animal_dict

for sentence in sentence_dict:
    for w in sentence_dict[sentence]:    
        for m in re.finditer(w,sentence):   
            sentence_dict[sentence][w].append(m.start(0))


print sentence_dict

它给了我以下输出，即它将值附加到字典中每个句子的每个列表中，而不仅仅是当前的：

{'the quick brown fox': {'tiger': [9], 'lion': [4, 0], 'fox': [16], 'elephant': [19, 10]}, \
'the lion, the witch and the wardrobe': {'tiger': [9], 'lion': [4, 0], 'fox': [16], 'elephant': [19, 10]}, \
'lion and tiger and elephant, oh my!': {'tiger': [9], 'lion': [4, 0], 'fox': [16], 'elephant': [19, 10]}, \
'ellie the elephant': {'tiger': [9], 'lion': [4, 0], 'fox': [16], 'elephant': [19, 10]}}

关于如何解决此问题的任何建议？提前致谢！

Answer 1

我假设您希望您的输出显示每个句子中出现动物名称的索引。

import re
sentence_list = ["the quick brown fox", "ellie the elephant", "the lion, the witch and the wardrobe", "lion and tiger and elephant, oh my!"]

animal_list = ["lion", "fox", "tiger", 'elephant']

sentence_dict = {}

for s in sentence_list:
  sentence_dict[s] = {}
  for a in animal_list:
    sentence_dict[s][a] = []

for sentence in sentence_dict:
    for w in animal_list:
        for m in re.finditer(w, sentence):
            sentence_dict[sentence][w].append(m.start(0))


print sentence_dict

以上代码有如下输出：

{'the quick brown fox': {'tiger': [], 'lion': [], 'fox': [16], 'elephant': []}, 'the lion, the witch and the wardrobe': {'tiger': [], 'lion': [4], 'fox': [], 'elephant': []}, 'lion and tiger and elephant, oh my!': {'tiger': [9], 'lion': [0], 'fox': [], 'elephant': [19]}, 'ellie the elephant': {'tiger': [], 'lion': [], 'fox': [], 'elephant': [10]}}

您的代码不起作用的原因是因为您的 animal_dict 中的列表是同一个对象，因此不是为每个句子/动物对保留单独的列表，每个动物在句子之间共享相同的列表。